emitterShape
The shape of the region of space where the system spawns new particles.
Declaration
var emitterShape: SCNGeometry? { get set }Discussion
To randomize the locations where new particles spawn, assign a geometry to this property. This geometry defines the shape of the space where new particles may spawn, and the birthLocation and birthDirection properties define locations within and directions relative to the shape. For example, assigning a sphere geometry causes particles to spawn at random locations along the surface of the sphere (or within the volume of the sphere, according to the birthLocation property).
The default value is nil, specifying that all new particles emit from a single point. For particle systems attached to a node, this point is the origin of the node’s coordinate system. For particle systems attached directly to a scene using the addParticleSystem(_:transform:) method, use that method’s transform parameter to specify the emission point.